Heat regulating device



06L 1931. 0-. GITAYLOR 1,827,340

HEAT REGULATING DEVICE Filed June 18, 928

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44 LAME IGNITION MEA N5 THERMQS T4 T 61-0555 WHEN #07 INVENTOR DANIEL 6. TAYLOR ATTORNEYS Patented Oct. 13, 1931 UNITED STATES PATENT OFFICE DANIEL G. TAYLOR, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO MINNEAPOLIS- HONEYWELL REGULATOR COMPANY, OF MINNEAPOLIS, MINNESOTA, A. CORPORA- TION OF DELAWARE HEAT REGULATING DEVICE Application filed June 18,

I the invention is to prevent explosion of the atomized fuel in case of the interruption of fuel supply during normal operation of the heating apparatus. A large number of burners now in use introduce the fuel into the fire pot in a finely atomized fog-like condition. If,'during the normal operation (with a supply of this atomized fuel present in a heated lire pot) the fuelsupply is cut off, and if an attempt is made to ignite it, violent explosion ordinarily results. One of the causes of fuel failure is the collection of the water in the fuel supply pipe, which momentarily interrupts the fuel flow over a suflicient length of time to extinguish the flame. On resumption of fuel supply, the pot is again filled with atomized fuel and if at this time ignition is supplied an explosion will result.

At the normal starting period when the apparatus is cold the atomized fuel, due to the cold condition does not remain in atomized form as long as it does under normal running conditions when the apparatus is hot. Therefore, at the initial starting period although the atomized fuel may be furnishedover a period'of from five to ten. seconds explosion does not occur. However, when the apparatus is heated, atomization is continued or is maintained over a longer period and the introduction of a spark or ignition at this period will cause explosion. this invention, as above stated, is to prevent such explosion.

Another important feature, in combination with the above mentioned feature, is the provision of a timing cycle at the end of which the apparatus will be conditioned, so that normal start cannot be made without inspection of the apparatus, and resetting of a timing switch to close a starting circuit or its equivalent.

Features of the invention include all the arrangements shown in all of the diagrams. as well as the conceptions of providing positively operating means controllable respectively by means which controls the burner apparatus and means which is operative as the result of flame at the burner apparatus, to prevent a closure of ignition contacts ()ne object of 1928. Serial No. 286,465.

whenever there is a fuel supply failure during normal operation, and to always close the ignition circuit when the motor circuit is open, and to condition it to remain closed as long as the motor circuit is open.

Features and advantages of the invention will be set forth in the description of the drawings forming a part of this application, and in said drawings Figure 1 is a diagrammatic viewshowing a simple application of'the invention; 7

Figures 2, 3 and 4; are detail views showing different positions of the ignition switch latch mechanism and control devices therefor; and

Figure 5 is a diagrammatic view showing another application of the invention in which a timing switch is employed along with a low voltage control circuit controlled by a room thermostat.

A simple application of the invention is shown in Figure 1 in which numerals 1 and 2 indicate respective main lines. An igni tion switch includes contacts 3 and 4.. The contact 4 is carried in this instance by a spring element 5 which normally occupies (under tension) the position shown, and is adapted to be forcibly moved (against spring tension) downwardly to open the contact. This element 5, as part of a latching mechanism, has an opening 6. The latching mechanism also includes the resilient element 7 which normally occupies the position shown in Figures 2, 8 and 5, and is adapted to be forcibly flexed to the left to cause its upper end 8 to engage in the opening 6 and permit the element 5 to automatically move to switch open position as shown in Figure 4. Although the construction of this latching mechanism is claimed, there is no intention to be limited to it. The element 7 is provided With a shoulder 9 which limits the downward movement of the switch arm 5. The elements 5 and 7 are, therefore, automatically movable one direction to assume the positions shown'in Figure 1. It will, of course, be understood that the elements 3, 5 and 7 are suitably insulated from one another. Element 5 is connected by conductor 10 with ignition means diagrammatically indicated at 11 and-the opposite side of this means is connected by conductor 12 with line 1. Contact 3 is connected by conductor 13 with conductor 14 which in turn is connected with relay armature or switch arm 15 operating against a contact 16, connected by conductor 17 with line 2. In this instance, instead of having the switch arm 15 operated manually, it is operated by an electro-magnetic device, the coil of which is indicated at 20, one side of the coil being connected by conductor 21 with line 1 and the other side connected by conductor 22 with the switch arm 23 operating against a contact 24, in turn connected by conductor 25 with line 2.

The elements 15 and 20 can be considered as partsof a magnetically operable switch. Two relays are employed in the present embodiment of the invention, as a convenient means for controlling the circuit, but there is no intention to be limited to" this particular form of switch control mechanism. The function of the second relay is to control its switch in response to presenceor absence of flame at the burner apparatus. Conductor 14 connects arm 15 with conductor 30, which, in turn, connects with one side of the burner apparatus and/or burner motor indicated at 31, and also with conductor 13. The other side of the motor is connected by conductor 32 with line 1. Thus whenever the motor line is energized, the ignition means 11 is also energized, if the contacts 3 and 4 are closed. The arm 15 has a suitablyinsulated extension 35 which is engageable with an insulated roller 36 carried by the arm 5 to throw the arm 5 to switch-closed position, as the arm 15 moves to the position shown in Figures 1 and 2 or as the coil 20 is de-energized. As shown, this arm engages the roller when the relay is de-energized under some condlbut may as well, tions, occupy the position shown in dotted lines at the right of the roller, because it will be noted that the element 7 is positively ho1d-. ing the element 5 in switch closed position. When the coil 20 is energized, the arm 35 oocupies a position shown in Figures 3 and 4 which permits automatic opening of the contacts 3 and 4 when the element 7 is moved to the position shown in Figure 4.

Thetsecond relay has a coil indicated at 40 and an armature indicated at 41. One side I of the coil is connected by a conductor 42 with a thermally operable member 43, operating against the contact 44 which contact is in turn connected by conductor 45 with line 2. Thus, there is included a thermally operable meansfor controlling the second relay as the result of heat supplied by the burner,

When contacts 43-44 close, relay coil 40 is energized and the armature is pulled in. The armature 41 in this instance has an extension or equivalent means 51 which operates the latch 7 (on response to flame and when relay 41 closes) to move it to the position shown in Figure 4, and permit the contacts .3 and 4 to open, and therefore interrupt the ignition circuit. It will be noted that this interruption always takes place whenever flame is obtained, and that no reclosure of 3, 4, can take place until the latch is released as result of engagement of 35 with 36 as the arm 15 falls away.

An important feature and conception is to stop operation of the ignition means as soon as flame is obtained, and to close the ignition circuit each time the motor or burner apparatus is rendered inoperative.

Operation Assume contacts 23 and 24 to close. Coil 20 is energized, contacts 1516 are made and the motor is energized through the circuit, including elements 2, 17, 16, 15, 14, 30, 31, 32, l. The ignition means is also energized through 2,17,16,15,14,13,3,4,5,10,11,12,1. After contacts 1516 have closed,the element 35 has assumed the position shown in Figures 3 and 4, so that when 15 moves in an opposite direction 35 will engage 36 to close contacts 3-4. Whatever the final positions of 35, thelatch element 7 will secure element 5 in contact closed position. However, the element 35 is so positioned at the end of its inward movement that if element 7 is moved to the position shown in Figure 4, the arm 5 is free to drop, inasmuch as it is tensioned to automatically move downwardly. If ignition is successful, contact 44 substantially immediately closes and coil 40 is energized, closing the relay 41 and causing the element 51 to engage element 7 as shown in Figure 4, pushing it to the left and releasing the element 5 and opening contacts 3 and 4.

Now suppose a failure of fuel and resulting disappearance of flame (elements are now positioned as shown in Figure 4, both switches closed). Coil 40 is de-energized, 41 swings to the right positioning the element 51 to permit a movement of the element 7 also to the right when released. Thus contacts 3 and 4 remain n open position, and ignition cannot be furnished while contacts 1615 are closed, and while the burner is running and fuel is-being furnished. Therefore, reignition is positively prevented when the burner pot is hot and there is atomized fuel therein. As long as the furnace is suficiently hot to maintain the thermal switch -4344 closed the igniter cannot be operated concurrently with the oil burner, because coil 40 remains energized to cause the switch 3 4 to assume the position shown in Figure 4 whenever the .oil burner is operative. The above described arrangement will be found particsecondary thermostatically controlled cir-' cuit, including a pilot relay which in turn controls current to the coil 20, and to the heating coil of the timing device, see F igure 5.

The form shown in Figure 5 includes some elements identical with those of Figure 1 and these elements, for convenience, have been given the same reference numerals as the corresponding parts in Figure 1.

In this form of the invention, a timing device and a low voltage control circuit have been introduced, this control circuit including a pilot relay in turn controlled by a room thermostat or similar device thermally operable. In this case, the relay coil 20 which controls the switch for energization of the motor or burner apparatus has one side connected by conductor with line 1 and the other side connected by conductor 61 with a heating coil 62 'of a thermally operable timing switch, in this instance a warp switch. The opposite side of the heating coil is connected by conductor 61 with a pilot relay switch arm 62, operating against contact 63 which contact in turn is connected by conductor 64 with line 2. It will be noted that the coils 20 and 62 are in series across the main line so that whenever the burner a pparatus control circuit is closed, coil 62 will receive heat. In addition, a shunt circuit is provided for the coil 62 and is adapted to be closed to prevent heating of the coil 62, whenever flame is present because at that time no safety timing operation is needed. The presence of flame will operate the relay coil 40 as in the first form of the invention. The shunt circuit includes conductor 66 connected with one side of the coil 62 and with switch arm 67 operating against contact 68 connected by conductor 69 with the opposite side of the heating coil. When armature 67 closes as the result of energization of coil 40, due to the presence of flame, the shunt circuit will be closed and coil 62 will be inoperative. The warp member of the switch is indicated at 70 and controls the pivoted switch arm 71 which has one side engaging the warp memher as at 72 and its o.her side engaging the contact 73. There is no intention to be limited to the particular form of timing device. The contacts 71 and 73 are, in this instance, part of a secondary control circuit, which includes a transformer having the primary 75 connected on one side with line 2 and on the other side with line 1, and the secondary 76 connected on one side by conductor 77 with contact 71, and on the other side by conductor 78 with one side of the coil 79 of the pilot relay or switch control device. The other side of this coil 79 is connected by conductor -mostat resulting in closing of BW by 80 to a conductor81, which latter conductor connects armatures 82.83 respectively operating against contacts 8485. The contacts 8385 are the starting contacts for the secondary circuit and the contacts 8284 are the holding contacts. The starting contact 85 is connected by conductor 87 with contact B of a room thermostat, the opposite contact of which is indicated at W. This room device includes a thermally responsive and movable element R having a portion sequentially engageable with contacts BVV in one order, and disengageable in reverse order. The holding contact 84 is connected by conductor 89 with element R. It will be seen that elements 15- 82 are controlled by relay coil 20 so that whenever this coil is energized, the burner apparatus or motor will receive current and the holding contact will close, and, although the fuel control means is not shown, fuel will be supplied. It will also be noted that the elements 41, 67, and 83 are controlled by coil 40 which is energized whenever flame is present, the result being that upon closure of the armature 41 the latch is moved to release the arm 5 to open contacts 3 and 4 and therefore interrupt the ignition circuit, the.

starting contact is broken (which will prevent a restart of the burner) and the shunt circuit is closed at 6768 to prevent operation of the'timing switch through its heating coil 62.

Operation for form of Figure 5 Suppose a call for heat by the room ther- R. Coil 79 is energized through the following circuit: 76, 7s, 79, s0, s1, s3, s5, 87, B, W, 90,-

73,71, 77, 76. On energization of 79, 62 closes energizing the heating coil 62, and the coil 20. The circuit is so simple in this case that it is not deemed necessary to trace it. Heat is now supplied to coil 62 and if, at the end of a predetermined time, ignition is not successful, element 70 will move in this instance to the left, releasing the arm 71 which will be pulled downwardly by the spring and break contact at 73, thus de-energizing relay 79 and opening switch 62 de-energizing coil 20, and opening switch 15 to stop the motor and open the holding contact. It will be noted that if the element 70 moves sufficiently to allow the switch to rock in direction of the arrow, the switch will open and the end of the switch will abut the side face of the element 7 O and lock the switch in open position. Thus the contacts 7173 can only be closed by manual operation. This is a safety feature which prevents a re-ignition period before mains substantially in the position shown in the drawings. Closing of the relay l5 positions the arm 35 as shown in Figure 3 so that the arm 5 is free to move to open its contacts, when the latch is properly operated by the flame responsive device. Due to presence of flame, coil 40 is now energized, 41 moves arm 51 and throws the latch to a position of Figure 4, opening the ignition circuit through contacts 3 and 4. It will now be assumed that the burner is operating properly, flame is being produced but that suflicient heat has not been supplied to the room to open contacts BW. Under these conditions suppose a fuel failure (the fuel supply means has not been shown but it is assumed that such means is present). Suppose a momentary supply failure from any cause. The apparatus or pot is now in a heated condition and there is vaporized unignited fuel therein. If, under these conditions, ignition could take place, there would be an explosion. It will, however, be seen that ignition cannot take place because contacts 3 and 4 are open and coil 20 is energized so that arm 35 cannot act to close contacts 3 and 4. Under these conditions after flame switch 43-44 cools and opens to de-energize coil 40, heating coil 62 is receiving current and at the end of a timing period, for example ten to fifteen seconds, element will move to the proper position, and 71 will break contact with 73, de-energizing coil 7 9 and causing a shut-down hv stopping the motor through opening of switch 15, due to de-energizatio-n of coil 20. When switch 15 opens, the arm 35 engages the roller 36, raises arm 5 to release the latch which latch again assumes the position shown in Figure 5. This is a safety condition, and the apparatus cannot be started until by manual re-setting of the element 71. During the period in which repair is made the atomized fuel settles and the pot cools suflicientlv so that when a normal start is made there is no danger of explosion.

Another very important application of the invention is shown in Figure 5, in which a thermally controlled timing device is em ployed, operative whenever the motor is energized to obtain opening of the motor circuit and shut down the burner apparatus at the end of a predetermined period if flame is not obtained during a trial ignition period. The main object, as before mentioned, is to avoid the introduction of a spark or flame by the ignition means, after flame failure except at a normal starting period, in other words, to avoid the introduction of heat or analogous ignition flame while the fire pot is charged with atomized fuel. It will be understood, as before stated, that the device is particularly applicable to burners in which the fuelis introduced in finely atomized fog-like condition, and in which if this highly atomized fuel is allowed to collect and is ignited, under certain conditions, there will be a violent explosion. One important purpose of the invention herein is, therefore, to prevent reignition in case flame fails during a normal operation of the device and while there is a call for heat which is maintaining the motor circuit in a closed position, and, therefore, in which the burner apparatus is operating and furnishing a spray of oil while in a heated condition.

I claim as my invention:

1. In a device of the class described, a burner apparatus and ignition means therefor including a switch, means for controlling the operation of the burner apparatus including mechanical means operable to close the ignition switch as the burner apparatus ceases to operate, and means operating to open the ignition switch as the result of flame produced by the burner apparatus.

2. In a device of the class described, a burner apparatus and ignition means therefor including a switch which moves automatically to one control position, means for controlling the operation of the burner appa rat-us including means operable to close the ignition switch as the 'burner apparatus ceases to operate, and means operable to release the ignition switch for opening movement as the result of flame produced by the burner apparatus, said switch having latching means arranged to lock the switch in closed position, as the burner apparatus ceases to operate, said latch means being operable by said flame responsive means to release the switch for an automatic opening.

3. In a device of the class described, a burner apparatus and ignition means therefor including a switch which opens automatically, latching means for the switch automatically operable to move to latching position when said switch closes, means for controlling burner operation and including means operating therewith to close the ignition switch as burner operation ceases, and means for operating the latching means to release said ignition switch for opening movement as the result of flame produced b the burner.

4. In a device of the class described, a burner apparatus and ignition means therefor including a switch which opens automatically, latching means for the switch automatically operable to move to latching position when said switch closes, means for controlling burner operation and including means operating therewith to close the ignition switch as burner operation ceases, and means for operating the latching means to open the ignition switch as the result of flame produced by the burner, a timing device arranged to be operative whenever the burner is operating and there is no flame and to stop burner operation at the end of a predetering coil, and a shunt circuit for the heating coil adapted to be closed only when there is flame at the burner and to be controlled by that means which operates the latching means as the result of flame produced by the burner.

5. A device of the class described including a burner apparatus, ignition means therefor including a switch, a second switch having circuit connections for controlling the burner apparatus, a third switch operable as the result of heat supplied by the burner, means operable by the second-switch to move the ignition switch to closed posi tion as the second switch opens, and means operable by the third switch to cause motion of the ignition switch to opened position when said third switch closes.

6. A device of the class described including a burner apparatus, ignition means therefor including a switch adapted to open automatically, a second switch having circuit connections for controlling the burner apparatus, a third switch operable as the result of heat supplied by the burner, means operable by the second switch to move the ignition switch to closed position as the second switch opens, and means operable by the third switch to cause motion of the ignition switch when said third switch closes.

7. A device of the class described including a burner apparatus, ignition means therefor including a switch and latch means associated with the switch to control it, a second switch having circuit connections for controlling the burner apparatus, a third switch operable as the result of heat supplied by the burner, means operable by the second switch to move the ignition switch to closed position as the second switch opens, and means operable by the third switch for moving the latching means to allow opening of the ignition switch when said third switch closes, said ignition switch being adapted to open automatically and said latching means being adapted to move automatically to hold the ignition switch in closed position after the closure of said ignition switch is obtained by the opening of said second switch.

8. A device of the class described including a burner apparatus, ignition means therefor including a switch, a second switch and a relay, electrical connections for controlling the burner apparatus through the second switch and thermally operable means for controlling the relay as the result of heat supplied by the burner, means operable by said second switch which controls the burner apparatus to close the ignition switch as said second switch opens, and means operable by the relay for causing opening of the ignition switch.

9. A device of the class described including a burner apparatus, ignition means therefor including a switch, a pair of switches first and second, electrical connections for controlling the burner apparatus through the first switch, thermally operable means for controlling the second switch as the result of heat supplied by the burner, means operable by that switch which controls the burner apparatus to close 1 the ignition switch as said first switch opens means operable by the second switch for causing opening of the ignition switch as said second switch closes, a timing device including a heating coil and energizable when the motor is energized, the first switch being controlled by the switch of said'timing device to open at the end of a predetermined timing period, and a shunt circuit for said heating coil controllable by said second switch to be closed when said second switch closes, to prevent operation of the timing device.

10. A device of the class described includ ing a burner apparatus, ignition means therefor including a switch automatically operable to open and latch means associated with the switch to control it, second and third switches, electrical connections for controlling the burner apparatus through the second switch, thermally operable means for controlling the third switch as the result of heat supplied by the burner, means operable by the second switch to move the ignition switch to closed position when said second switch opens and to condition said switch for opening when said second switch closes, means operable by the third switch for moving the latch means to permit opening of the ignition switch as said third switch closes, a timin device including a heating coil and energize when the motor is energized, the switch of said timing'device being arranged to open the second switch at the end of a timing cycle, the timing device being arranged to lock its switch in open position, and a shunt circuit for said heating coil controllable by said third switch to be closed when said third switch closes, to prevent operation of the timing device.

11. A device of the class described including a burner apparatus, ignition means therefor including aswitch-automatically operable to open, and latch means associated with the switch to control it, a pair of relays first and second, electrical connections for controlling the burner apparatus through the first relay, and thermally operable means for controlling the second relay as the result of heat supplied by the burner, means operable by that relay which controls thecburner apparatus to secure the switch in closed position when the relay is open, and to release said switch for opening when said relay closes, and means operable by the second relay for moving the latch means to permit opening of the switch as the second relay closes. v

12. A device of the class described includ ing a burner apparatus, ignition means therefor including a switch automatically operable to open and latch means associated with the switch to control it, a magnetically operable switch and a relay, electrical connections for controlling the burner apparatus through the magnetic switch and thermally operable means for controlling the relay as the result of heat supplied by the burner, means operable bv the magnetic switch which controls the burner apparatus to secure the ignition switch in closed position when the magnetic switch is open and therefore when the burner apparatus is not running and to release said ignition switch for opening when said magnetic switch closes. and means operable by the relay for movingthe latch means to permit opening of the ignition switch as the relay closes.

13. A device of the class described includinga burner apparatus. ignition means therefor including a switch haying latch mechanism for controlling the same. a second switch and a relay. electrical connections for controlling the burner a paratus through the second switch. thermally o erable means for controllin the relay switch as the result of heat supplied by the burner. means o erable by the second switch to close the ignition switch and condition the latch mechanism to hold the ignition switch closed as the second switch o ens. and means operable by the relay switch for moving the latch means to permit opening of the ignition switch as the third relay closes.

14. A device of the class described including' a burner apparatus. ignition means therefor i cludin a swit h and latch means associated with the switch to secure the switch in closed position. a second sw ch h ving circuit connections for controlling the burner a paratus. and a relay operable as the result of heat supplied by the burner. means o erable by the second switch to move the ignition switch to closed position as said second switch ope s. and means operable by the relay for m v n the latch ng means to obtain o ening of e gnition switch. as sa d rela closes.

1.5. In adevice of the class described. a burner a aratus and ignition means therefor including a switch. means for controlling operation of the burner apparatus including mechanical means operable for closingthe ignition switch as the burner apparatus ceases to operate, and mechanical means operating to open the ignition switch as the result of flame produced by the burner apparatus.

16. In a device of the class described, a burner apparatus and ignition means therefor including a switch biased to open, latching means for holding the switch closed, means for controlling burner operation and including means operating to close the ignition switch as burner operation ceases, and means for operating the latching means to release the ignition switch as the result of flame produced by the burner.

In witness whereof, I have hereunto set my hand this 14th day of June, 1928.

DANIEL G. TAYLOR. 

